Arsenopyrite-Marcasite with Siderite and Muscovite

Minas da Panasqueira, level 3, Aldeia de São Francisco de Assis, Covilhã, Castelo Branco, Cova da Beira, Centro  Portugal (1999)

Specimen size: 13.4 × 8.8 × 3 cm = 5.28” × 3.46” × 1.18”
Main crystal size: 3 × 2.6 cm = 1.18” × 1.02”